[src/netbsd-8]: src/sys/ufs/ffs Pull up following revision(s) (requested by k...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8e95fb5ada9b
branches:  netbsd-8
changeset: 451636:8e95fb5ada9b
user:      martin <martin%NetBSD.org@localhost>
date:      Wed May 29 15:51:40 2019 +0000

description:
Pull up following revision(s) (requested by kardel in ticket #1272):

        sys/ufs/ffs/ffs_alloc.c: revision 1.164

PR/53990, PR/52380, PR/52102: UFS2 cylinder group inode allocation botch

Fix rare allocation botch in ffs_nodealloccg().

Conditions:
    a) less than
         #_of_initialized_inodes(cg->cg_initediblk)
         - inodes_per_filesystem_block
       are allocated in the cylinder group
    b) cg->cg_irotor points to a uninterupted run of
       allocated inodes in the inode bitmap up to the
       end of dynamically initialized inodes
       (cg->cg_initediblk)

In this case the next inode after this run was returned
without initializing the respective inode block. As the
block is not initialized these inodes could trigger panics
on inode consistency due to old (uninitialized) disk data.

In very rare cases data loss could occur when
the uninitialized inode block is initialized via the
normal mechanism.

Further conditions to occur after the above:
    c) no panic
    d) no (forced) fsck
    e) and more than cg->cg_initediblk - inodes_per_filesystem_block
       allocated inodes.

Fix:

Always insure allocation always in initialized inode range
extending the initialized inode range as needed.

Add KASSERTMSG() safeguards.

ok hannken@

diffstat:

 sys/ufs/ffs/ffs_alloc.c |  44 +++++++++++++++++++++++++++++++++++---------
 1 files changed, 35 insertions(+), 9 deletions(-)

diffs (107 lines):

diff -r 69cc6e26ccbb -r 8e95fb5ada9b sys/ufs/ffs/ffs_alloc.c
--- a/sys/ufs/ffs/ffs_alloc.c   Wed May 29 15:47:05 2019 +0000
+++ b/sys/ufs/ffs/ffs_alloc.c   Wed May 29 15:51:40 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ffs_alloc.c,v 1.156.6.1 2017/07/24 06:21:57 snj Exp $  */
+/*     $NetBSD: ffs_alloc.c,v 1.156.6.2 2019/05/29 15:51:40 martin Exp $       */
 
 /*-
  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ffs_alloc.c,v 1.156.6.1 2017/07/24 06:21:57 snj Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ffs_alloc.c,v 1.156.6.2 2019/05/29 15:51:40 martin Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_ffs.h"
@@ -1259,7 +1259,7 @@
        struct buf *bp, *ibp;
        u_int8_t *inosused;
        int error, start, len, loc, map, i;
-       int32_t initediblk;
+       int32_t initediblk, maxiblk, irotor;
        daddr_t nalloc;
        struct ufs2_dinode *dp2;
        const int needswap = UFS_FSNEEDSWAP(fs);
@@ -1271,7 +1271,13 @@
                return (0);
        mutex_exit(&ump->um_lock);
        ibp = NULL;
-       initediblk = -1;
+       if (fs->fs_magic == FS_UFS2_MAGIC) {
+               initediblk = -1;
+       } else {
+               initediblk = fs->fs_ipg;
+       }
+       maxiblk = initediblk;
+
 retry:
        error = bread(ip->i_devvp, FFS_FSBTODB(fs, cgtod(fs, cg)),
                (int)fs->fs_cgsize, B_MODIFY, &bp);
@@ -1291,7 +1297,8 @@
         * Check to see if we need to initialize more inodes.
         */
        if (fs->fs_magic == FS_UFS2_MAGIC && ibp == NULL) {
-               initediblk = ufs_rw32(cgp->cg_initediblk, needswap);
+               initediblk = ufs_rw32(cgp->cg_initediblk, needswap);
+               maxiblk = initediblk;
                nalloc = fs->fs_ipg - ufs_rw32(cgp->cg_cs.cs_nifree, needswap);
                if (nalloc + FFS_INOPB(fs) > initediblk &&
                    initediblk < ufs_rw32(cgp->cg_niblk, needswap)) {
@@ -1307,6 +1314,9 @@
                            FFS_NOBLK, fs->fs_bsize, false, &ibp);
                        if (error)
                                goto fail;
+
+                       maxiblk += FFS_INOPB(fs);
+                       
                        goto retry;
                }
        }
@@ -1316,14 +1326,22 @@
            (fs->fs_old_flags & FS_FLAGS_UPDATED))
                cgp->cg_time = ufs_rw64(time_second, needswap);
        inosused = cg_inosused(cgp, needswap);
+       
        if (ipref) {
                ipref %= fs->fs_ipg;
-               if (isclr(inosused, ipref))
+               /* safeguard to stay in (to be) allocated range */
+               if (ipref < maxiblk && isclr(inosused, ipref))
                        goto gotit;
        }
-       start = ufs_rw32(cgp->cg_irotor, needswap) / NBBY;
-       len = howmany(fs->fs_ipg - ufs_rw32(cgp->cg_irotor, needswap),
-               NBBY);
+
+       irotor = ufs_rw32(cgp->cg_irotor, needswap); 
+
+       KASSERTMSG(irotor < initediblk, "%s: allocation botch: cg=%d, irotor %d"
+                  " out of bounds, initediblk=%d",
+                  __func__, cg, irotor, initediblk);
+
+       start = irotor / NBBY;
+       len = howmany(maxiblk - irotor, NBBY);
        loc = skpc(0xff, len, &inosused[start]);
        if (loc == 0) {
                len = start + 1;
@@ -1341,9 +1359,17 @@
        if (map == 0) {
                panic("%s: block not in map: fs=%s", __func__, fs->fs_fsmnt);
        }
+       
        ipref = i * NBBY + ffs(map) - 1;
+
        cgp->cg_irotor = ufs_rw32(ipref, needswap);
+
 gotit:
+       KASSERTMSG(ipref < maxiblk, "%s: allocation botch: cg=%d attempt to "
+                  "allocate inode index %d beyond max allocated index %d"
+                  " of %d inodes/cg",
+                  __func__, cg, (int)ipref, maxiblk, cgp->cg_niblk);
+
        UFS_WAPBL_REGISTER_INODE(ip->i_ump->um_mountp, cg * fs->fs_ipg + ipref,
            mode);
        /*